Mechanism for withdrawing and winding yarn in spinning units

ABSTRACT

Mechanism for withdrawing and winding yarn from spinning units, said mechanism having a novel combination of elements including a self-threading yarn guide. The mechanism includes in that order a pair of rollers for withdrawing yarn from the outlet of the spinning unit, a self-threading guide, a tension compensator, and a means for winding a bobbin including a yarn traverse and laying mechanism. The configuration and placement of the self-threading guide are such that after breakage or depletion of the yarn, yarn delivery may be resumed with yarn traveling from the outlet of the spinning unit past the self-threading guide to the yarn traverse, without passing between the yarn withdrawing rollers. Continued yarn traverse and take-up by the bobbin automatically threads the yarn through the self-threading guide and introduces it between the yarn withdrawing rollers.

United States Patent Brazda, deceased et al.

1451 June 20, 1972 MECHANISM FOR WITHDRAWING AND WINDING YARN IN SPINNING UNITS Inventors:

Assignee:

Filed:

Appl. No.:

Ladislav Brazda, deceased, late of Cerveny Kostelec by Drahuska Brazdova, Dagmar Brazdova, Heirs; Miloslav Prochazka, Nachod; Vladimir Kuhn, Velke Svatonovice; Josef Ozdian, Cerveny v Kostelec; Rudolf Benes, Trubejov U Nachoda, all of Czechoslovakia Elitex, Zavody textr'lniho strojirenstvi, Liberec, Czechoslovakia Feb. 26, 1970 Foreign Application Priority Data March 7, I969 Czechoslovakia 1676/69 US. Cl. ..57/34 R, 57/58.89 Int. Cl ..D0lh 13/04, DOlh 15/00 Field of Search ..57/34 R, 58.89-58.95,

[56] References Cited UNITED STATES PATENTS 3,354,626 ll/l967 Cizek et al. ..57/58.89 X 3,354,627 11/1967 Cizek et al. ...57/58.89 X 3,438,187 4/1969 Escursell-Prat ..57/34 R Primary Examiner-John Petrakes Attorney-Arthur O. Klein [57] ABSTRACT Mechanism for withdrawing and winding yarn from spinning units, said mechanism having a novel combination of elements including a self-threading yarn guide. The mechanism includes in that order a pair of rollers for withdrawing yarn from the outlet of the spinning unit, a self-threading guide, a tension compensator, and a means for winding a bobbin including a yarn traverse and laying mechanism. The configuration and placement of the self-threading guide are such that after breakage or depletion of the yarn, yarn delivery may be resumed with yarn traveling from the outlet of the spinning unit past the self-threading guide to the yarn traverse, without passing between the yarn withdrawing rollers. Continued yarn traverse and take-up by the bobbin automatically threads the yarn through the self-threading guide and introduces it between the yarn withdrawing rollers.

6 Claims, 3 Drawing Figures PLA'TENTEDauRzo m2 3,670,484

SHEEI 1 or 2 8'9. x IIVVEIVTORS= Ladislav BRA ZDA Nilosfm PROC/MZKA ATTORNEY MECHANISM FOR WITI-IDRAWING AND WINDING YARN IN SPINNING UNITS The present invention relates to a mechanism for withdrawing and winding yarn in spinning units of machines for producing yarn, and more particularily relates to a combination of a spinning unit with a self-threading guide for the yarn winding mechanism. In previously known combinations of spinning units and yarn withdrawing and winding mechanisms there has been effort to secure the largest possible bobbin as the end product of the whole process. For this purpose, bobbins with cross yarn windings are preferred. It can thus be seen that there is a certain similarity between the end phase in the processing of yarn in such machines and cross winding machines. Although the final products of the two machines, i.e., the cross wound bobbins, are the same, the elements of winding mechanism for making cross wound bobbins can not be applied directly to spinning machines of the above indicated type.

The main reason for the above is the fact that the yarn produced by the spinning machines is treated in a manner which is quite different from that being wound by the winding machines. In order that yarn produced by the spinning machines shall be uniform, it must be withdrawn from the machines at a constant velocity. In winding machines, on the other hand, small variations in velocity of the yarn does not effect its quality, or the quality of the winding built up from such yarn. Because of the requirement that yarn be withdrawn from the spinning unit at a constant speed, in a winding and take-up mechanism associated with the spinning unit there is employed a pair of withdrawing rollers which firmly grip the yarn between them to withdraw the yarn from the outlet tube of the spinning unit, the yarn traveling from such rollers through the yarn traverse and laying mechanism. A further yam guide, in the form of a tension compensator, is disposed in advance of the yarn traverse, there being a further guide disposed on the exit side of the yarn withdrawing rolls. The necessity of using these elements has increased the labor of the attendants, particularily in the case of yarn breakage since with spinning machinery of the type indicated which has been hereto known fresh yarn or a yarn in which a break has been repaired has had to be guided manually between the withdrawing rollers and through the yarn guide disposed at the exit side of such rollers.

The mechanism according to the present invention has among its objects the removal or substantial removal of the above described disadvantages of hereto known devices. Such mechanism simplifies and speeds up the maintenance of the spinning unit, simultaneously eliminating the necessity for manually guiding the yarn between the withdrawing rollers after removing a yam breakage, and of guiding the yarn into the yarn guide disposed immediately on the exit side of the withdrawing rollers. Briefly, the mechanism in accordance with the present invention makes the guide which is disposed between the withdrawing rollers and the tension compensator self-threading, such guide being so disposed that at the same time as it threads itself it inserts the yarn between the two withdrawing rollers.

Further features of the mechanism according to the present invention are disclosed in the following specification and shown in the accompanying drawings of an illustrative embodiment of the mechanism, of which:

FIG. 1 is a view in prospective of the illustrative mechanism in accordance with the present invention;

FIG. 2 is a fragmentary view in end elevation of the mechanism shown in FIGJ, the view being taken from the line 22 of FIG. 1; and

FIG. 3 is a schematic view in front elevation of the mechanism shown in FIGS.1 and 2.

The drawings show the yarn outlet of one spinning unit and the yarn withdrawing and laying mechanism therefor. It will be understood that in a commercial installation a spinning machine will include a great number of such combinations disposed along the length of the machine. It is obvious that the description of only one of such combinations will suffice.

The mechanism of the present invention is illustrated herein in connection with a spinning unit of the pneumo-mechanical type, wherein the spinning of the yarn is carried out under pressure in a spinning chamber. It will be understood, however, that in its broadest aspects the invention is not limited to use with spinning units of such type. Since such pressure spinning chambers are old, only the yarn delivery tube 2 thereof is shown. Yam 1 issuing from tube 2 normally passes in a path N (FIGJ) between a first elongated driven withdrawing roller 3 and a shorter cooperating roller 4 forming a nip therewith. A self-threading yarn guide 5, to be described in detail hereinafter, is disposed at the exit side of the yarn withdrawing rollers 3, 4; guide 5 has an opening 14 therethrough through which the yarn I passes upwardly to engage a tension compensator 6 which is affixed to an apron l8 (FIGJ) of the machine. The tension compensator 6 is in the form of a shallow, smoothly bent outwardly convex rod which is symmetrical in opposite directions from its center C. The compensator has an effective length extending from the end 6a of the curved part thereof at one end to the similar end 6a at the other end. The tension compensator, which is conventional, compensates for the different lengths of yarn required as the yarn is laid upon a bobbin 9 by a yarn laying traverse mechanism. The bobbin is rim driven and supported upon a driven shaft 10, the traverse mechanism having a reciprocable slide 8, driven by conventional mechanism (not shown), slide 8 having a yarn receiving slot 7 therein.

The selfthreading yarn guide 5 is in the form of a plate which is fixedly mounted relative to the rollers 3, 4 and the tension compensator 6, the plate being inclined as shown in FIGS. 1 and 2 in an upward direction from the front or forward surface 12 thereof to the rear surface 13. The body plate of the guide 5 is substantially symmetrical about a central axis parallel to the axis of the roll 3. Thus, the forward and rear edge surfaces 12 and 13 of the guide 5 are of substantially the same configuration, the two such surfaces forming a composite guide surface which is convex in the direction from right to left in FIG.1, the two surfaces 12 and 13 meeting in an apex 11 which is disposed axially outwardly beyond the left hand end of roll 4 FIGS. 1 and 3). lnterrnediate the length of the rear guide surface 13 there is provided a yarn receiving slot 15 which is inclined forwardly in the direction from left to right in FIG. 1. Slot 15, which leads inwardly to the passage 14, has a shallow rear shoulder 16 at the right hand edge of the slot, whereby the traveling from left to right along the guide surface 13 and below guide plate 5 is led into the slot 15 and thence into the opening 14.

In the operation of the mechanism the yarn traverse 8 reciprocates between limits, at the left hand limit the yarn guiding slot lying in the position 7 as shown in FIG. 3, and at the right hand terminus of the reciprocation such slot lying in the position 7'. When the yarn 1 does not pass between the rollers 3, 4, and the yarn traversing slot lies in its right hand terminal position 7 the yarn passes along the path 0 above plate 5 (FIG. 3), being prevented from escape from the right hand end of the surface 12 of guide plate 5 by a forwardly projecting short finger 17. In such path a the yarn 1 is at the effective right hand end 6a of the tension compensator 6. A line a connecting the outlet tube 2 and the left hand terminal position 7 of the yarn traverse slot is shown in FIGS. Line a is substantially tangential to the left hand effective end 6a of the tension compensator 6. In order to enable the abovedescribed mechanism to work properly in the manner to be described below, it is necessary to dispose the body plate of the guide 5 in such manner that its apex l 1 lies outside the line a,. In the yarn path Q in which the yarn engages the center C of the tension compensator 6.

The above-described mechanism in accordance with the present invention functions as follows:

During normal operation the yarn 1 which escapes from the outlet tube 2 of the spinning unit passes between the withdrawing rollers 3, 4 and is fed by them through the passage 14 of the self-threading guide 5 and over the tension compensator 6. After passing over the tension compensator,

the yarn goes into the traversing slot 7 and is wound in cross wound fashion upon the bobbin 9 which is driven by the bobbin supporting roll 10. The operations conducted upon a breakage in the yarn are substantially the same as those which occur when one bobbin 9 has been filled and is replaced by an empty bobbin, so far as the path of yarn is concerned. Taking a case of yarn breakage as typical, after the yarn breakage has been repaired, the yarn, now free of engagement between the rollers 3, 4, is dropped into a path from the tube 2 to the yarn receiving guide slot 7. One such path is indicated at b in FIG.3. Assuming that the yarn traverse 8 is then going to the right, such member completes its travel in that direction so that the yarn momentarily passes along the path a and above guide plate 5. Upon the reverse travel of the traverse 8 the yarn progressively travels to the left along the forward guide surface 12 of the guide until the slot 7 of the traverse mechanism reaches its left hand terminal position'The yarn 1 then extends from the tube 2 into engagement with the edge surface 12 of the guide 5 thence into engagement with the low point 6a at the left of the tension compensator 6, and finally to the guide slot 7 of the yarn traverse mechanism. The tension of the yarn pulls it momentarily into a path P in which it engages the apex point 11 of the guide 5; immediately thereafter the tension in the yarn causes it to slip past the apex point 11 to assume a path shown by line a under the guide plate 5 and down the rear guide surface 13 and into contact with the overhang or shoulder 16 on the rear surface of the guide. During such action the yarn is placed in alignment with and to the left of the nip between the rollers 3, 4; consequently, upon the tightening of the yarn as it rides up over the higher central portion of the tension compensator 6 the yarn is not only pulled axially inwardly between the rollers 3, 4 but it is caused to enter the inclined slot 15 in the guide 5 and thus to be stabily positioned within the yarn receiving passage 14 in the guide.

Although the invention has been illustrated and described with reference to one preferred embodiment thereof, it is to be understood that it is in no way limited to the details of such an embodiment but is capable of numerous modifications within the scope of the appended claims.

What is claimed is:

1. In combination with a spinning unit for the manufacture of yarn, said unit having a yarn outlet, mechanism for withdrawing and winding yarn issuing from said outlet, said mechanism comprising in that order a pair or rollers for withdrawing yarn from said outlet, a self-threading stationary yarn guide having a yarn guiding opening therethrough, a yarn tension compensator, and means for winding a bobbin including a yarn traverse having a reciprocable yarn guide and a yarn laying mechanism, the yarn tension compensator being of shallow convex bow shape extending in a direction parallel to the path of reciprocation of the reciprocable yarn guide, the reciprocable yarn guide, the yarn tension compensator, and the stafionary yarn guide cooperating automatically to thread a yarn initially passing from the yarn outlet to the reciprocable yarn guide into the self-threading stationary yarn guide, the self-threading stationary yarn guide having a body extending generally in the direction of reciprocation of the reciprocable yarn guide, the body having a convex configuration with an apex at one end thereof, the body having a rear yarn guiding surface, further from the normal path of the yarn travelling from the withdrawing rollers to the opening through the stationary yarn guide, and a forward yarn guiding surface closer to the said normal path of the yarn, the body of the selfthreading guide having a yam-receiving slot extending from the forward yarn guiding surface thereof into the yarn guiding opening therethrough.

2. The combination according to claim 1, wherein the selfthreading guide is disposed close to the yarn withdrawing rollers, and the threading of a yarn into the self-threading guide introduces the yarn in a direction axially of the yarn withdrawing rollers between said rollers.

3. The combination of claim 1, wherein the apex of the body of the self-threading guide is disposed in a direction axialiy of the yarn withdrawing rollers outwardly beyond the path 0 the yarn between the yarn outlet and an end of the tension compensator in a direction parallel to the path of movement of the yarn traverse guide.

4. The combination according to claim 3, wherein the apex of the self-threading guide is not disposed substantially further axially outwardly than the path which the yarn takes when travelling directly from the yarn outlet to the yarn traverse guide.

5. The combination according to claim 4, wherein the apex of the self-threading guide is disposed between the path of the yarn when travelling from the outlet to the said end of the tension compensator and the path of the yarn when traveling in the center of the stroke of the yarn traverse guide.

6. The combination according to claim 3, wherein the body of the self-threading guide is in the form of a plate, said plate being tipped so that its rear yarn guiding surface lies closer to the yarn outlet than its forward yarn guiding surface. 

1. In combination with a spinning unit for the manufacture of yarn, said unit having a yarn outlet, mechanism for withdrawing and winding yarn issuing from said outlet, said mechanism comprising in that order a pair or rollers for withdrawing yarn from said outlet, a self-threading stationary yarn guide having a yarn guiding opening therethrough, a yarn tension compensator, and means for winding a bobbin including a yarn traverse having a reciprocable yarn guide and a yarn laying mechanism, the yarn tension compensator being of shallow convex bow shape extending in a direction parallel to the path of reciprocation of the reciprocable yarn guide, the reciprocable yarn guide, the yarn tension compensator, and the stationary yarn guide cooperating automatically to thread a yarn initially passing from the yarn outlet to the reciprocable yarn guide into the self-threading stationary yarn guide, the self-threading stationary yarn guide having a body extending generally in the direction of reciprocation of the reciprocable yarn guide, the body having a convex configuration with an apex at one end thereof, the body having a rear yarn guiding surface, further from the normal path of the yarn travelling from the withdrawing rollers to the opening through the stationary yarn guide, and a forward yarn guiding surface closer to the said normal path of the yarn, the body of the self-threading guide having a yarn-receiving slot extending from the forward yarn guiding surface thereof into the yarn guiding opening therethrough.
 2. The combination according to claim 1, wherein the self-threading guide is disposed close to the yarn withdrawing rollers, and the threading of a yarn into the self-threading guide introduces the yarn in a direction axially of the yarn withdrawing rollers between said rollers.
 3. The combination of claim 1, wherein the apex of the body of the self-threading guide is disposed in a direction axially of the yarn withdrawing rollers outwardly beyond the path of the yarn between the yarn outlet and an end of the tension compensator in a direction parallel to the path of movement of the yarn traverse guide.
 4. The combination according to claim 3, wherein the apex of the self-threading guide is not disposed substantially further axially outwardly than the path which the yarn takes when travelling directly from the yarn outlet to the yarn traverse guide.
 5. The combination according to claim 4, wherein the apex of the self-threading guide is disposed between the path of the yarn when travelling from the outlet to the said end of the tension compensator and the path of the yarn when traveling in the center of the stroke of the yarn traverse guide.
 6. The combination according to claim 3, wherein the body of the self-threading guide is in the form of a plate, said plate being tipped so that its rear yarn guiding surface lies closer to the yarn outlet than its forward yarn guiding surface. 